Power-driven compressor device



Dec 22, 1954 E. P. BURION ETAL. 3,162,357

POWER-DRIVEN COMPRESSOR DEVICE Filed June 12, 1962 2 Sheets-Sheet 1 Dec.22, 1964 E. P. BuRloN ETAL 3l62357 POWER-DRIVEN COMPRESSOR DEVICE FiledJune 12. 1962 2 Sheets-Sheet 2 r l l l l f L J a s i i.

United States Patent O 3,162,357 PWER-DRIWN CUMPRESSGR DEVICE EtiennePhilippe Burion, La Fratte, Isere, France, and Ren Antoine MichelrEoesca, Robin Dell Rl). 1, Boyertown, Pa.

Filed June 12, 1962, Ser. No. 201,981 Claims priority, applicationFrance, `lune 22, 1961, 865,767, Patent 1,300,305 6 Claims. (Cl. 23d-56) The present invention relates to a new free piston machine, intendedmore particularly to be used for compressing air to be employed forsupplying various receiving mechanisms.

The invention applies, nevertheless, to devices for cornpressing othergases, and is also applicable to devices such as gas generators orgasiers, that Vis to say, devices in which the energy produced by lthemotor element serves to Vcompress and to feed a mass of air at apressure which can be varied, the mass of air being utilized at leastpartly for the scavenging and the feeding of said motor element, saidenergy being nally collected in the form of heat and pressure in theexhaust gases which are utilized in a machine such as a turbine.

It is an object of the present invention to create a new machine whichis simple of structure and effective in operation and as compact aspossible.

It is another object of the invention to provide a machine wherein thenumber of movable parts is reduced with respect to the number of movableparts of similar machines.

It is a particular specific object of the invention to eliminatesynchronizing mechanisms for the regulation of movable parts, whichsynchronizing mechanisms are provided in the known art.

It is another further object of the invention to provide la machine ofthe type specied which is easily cooled only by circulation of air, suchair being caused to rapidly circulate onto the more heated parts of themachine without the aid of any blower or similar device.

According to the invention, the power-driven compressor comprises ahollow body divided into two variable volume compartments by a diaphragmassociated on one slide with at least one motor piston movable in amotor cylinder of the two-stroke Diesel cycle type, said diaphragmIbeing subjected on its other side to a damping caused by thecompressionwork of a charge of a `gas to be compressed and to aresilient stress developed by Ia charge of gas, the compression of whichcauses the return stroke of said diaphragm and motor piston.

The diaphragm advantageously is formed by a piston placed inside acylinder this piston conning inside said cylinder two variable volumechambers in which air is successively sucked in and compressed, one ofsaid chambers communicating with a collector vfor exhaust compressed airleading to an utilization device, and the other chamber communicating byan intermediate housing with scavenging -ports of the Diesel two-strokecylinder into which slides said motor piston which is rigidly connectedto said piston forming the diaphragm.

Various other characteristics of the invention will moreover be revealedby the detailed description and claims which follow.

Forms of embodiment of the invention are shown, by Way ofnon-restricting examples, in the attached drawings in which:

3,152,357 Patented Dec. 22, 1964 FIGURE 1 is a longitudinal crosselevation showing one form of embodiment of the power-driven compress-oraccording to the invention. v

FIGURE 2 -is a section at a smaller scale seen substantially along theline II-II of FIGURE 1.

FIGURE 3 is a section at a smaller scale taken substantially along theline III-HI of FIGURE 1.

FIGURE 4 is a partial diagrammatical section seen substantially alongtheline IV-IV of FIGURE 1.

FIGURES 5 and 6 are diagrammatical elevation-sections, showing twoalternative embodiments of the device.

As shown by the drawing, and more particularly, FIf URE 1, the freepiston machine device comprises a main casing 1, hereafter calledcompression casing, which internally delimits a cylinder 2, saidcompressor casing further being provided on -its periphery with coolingiins 3. At one of its ends, that shown to the right of FIGURE l, thecasing 1 supports a sheath 4 coniining a cylinder 5 and a collector 6communicating with the interior of the cylinder 2 by at least one outletflap-valve 7. The cylinder 5, formed by the sheath 4, is closed at itsend by a part 8 and also conlined by a collar 9 intended to contain amechanism 16 whose function is explained in the following description.As shown by the drawings, the sheath assembly 4 extends from aprojecting annular lrim 11 which is provided at the end of said cylinder2.

A projecting annular border 12, whose peripherie rim contines a strap orlilange, preferably extends obliquely in relation to the axis of thecylinder 2 and projects to a greater extent than that of the tins 3 withwhich this cylinder is provided. The middle part 'of the border 12 actsfor supporting inlet nap-valves 13. Other inlet llapvalves 14 are alsoprovided in the casing 1 near to the annular rim 11, which is used, aswell as the annular border 12, for maintaining a cylindrical part 1Scomprising, at its middle part, a porous element 16, so that said part15 thus `forms a filtering cartridge confining, with the periphery ofthe casing 1, a chamber 17 acting for channelling the air intended topass during the working of the device, in directions whereby this airraises the inlet riapvalves 13 or 14 respectively.

The peripheric strap or flange formed by the projecting border 12 isused for screwing a second casing 1S, hereafter called driving casing.The side of the driving casing turned towards the compressing casing isclosed by a partition 19 in which openings 20 (FIG. 2) are provided forpositioning Hap-valves 21 intended to enable a chamber 22 tocommunicate,confined between the compression and driving casings 1 and 1S, with Iacollector 23 provided in said casing 1S. f

In addition to the openings 20, the partition 19 coniines themouthportion of two cylinders 24 and 2S. The cylinders 24 and 25, `aswell as the other parts, both for the driving casing 18 as well as thecompression casing 1, are advantageously made of light metal alloys.Inside said cylinders, a lining is provided that may be made of a hardmetal, for example, of hard chromium, or of a castiron addition, orelse, as shown in the drawing, by the insertion of thin linings 26.

The two cylinders 24 and 25 are provided on their periphery and overmost of their length, with cooling ns 27. Moreover, the front part ofthe two said cylinders communicates, by a large dimensioned duct 28,called transfen Furthermore, the cylinder 25 also communicates with thecollector 23 through ports 29 advantaenging air of the cylindersraswi1l-beexplained farther denotes anexhaust manifold provided in thedriving casing, this exhaust :manifold communicating withv the interiorof the cylinder 24, by ports'lsl.V The terminal part of the cylinders24, 25, Le., that showing at the left part of FIGURE 1, is closed bymeans of a iinned cylinder head 32 in which, as shown in particular inFIGURE 4, ducts 33, 34 are provided, communicating injector 36of a knowntype is iixed, whose `working is subjected to the pressure prevailing inthe driving cylinders, the delivery. variation being regulated, for

example as i known .per se, by a pneumatic regulatorv sensitive tolthedeliveryy pressure-.of --the machine. This regulatorV being wellknown initself and consequently Vit is no more described since'it doers notconstitute structurally a part of the invention. be controlledby,electrically operated Vmechanism estimating the position of the mobileunit which is described hereafter. n f Y The various cylinders describedabove, which Vconfine both the compression casingl as well as thedriving casing 18, act as a housing for a' single mobile unit, which, inthe example shown, comprises a compressor pistonV 37 between the chamber22 and the interior of the cylinder. 2, this compressor pistonsupporting, on theone hand,"a-

piston 38 engaged in the cylinder 5, contined by the sheath 4, and onethe other hand, two driving pistons 39 and 40 placed in the cylinders24`and 25, as shown in particularin FIGURE 1. f

It is` advantageous that which are confined inside the cylinders y24,`25 between the pistons 39, 40 and the cylinder head 32 and which.

are denoted by the reference numerals 41 and 42,1have fthe combustionchambers This return stroke in the opposite directionl to thatof thearrow f1, thus causes( the compression of the air previously admitted'into the .chamber 22; this air is thus progressively deliveredthroughthe flap-valves 21 into the scavenging manifold 23 where itiscompressed, seeing that a'tjth-ismoment, the piston 40 closes theports As can be clearly seen from thedrawing, at the end of Y f thedriving stroke, i.e., the one in the direction ofthe arrow f1 theypiston 39 progressively exposes the exhaust .ports 31, so that'A theburnt ygases in the cylinder V24 can thus escape towards the manifold30. This also applies with each other and with a channel in which apumpf This injector can also to the burnt gases-inthe cylinder 25,.seeing thatthe tionexists between the two said'cylinders. At the momentwhen the piston 40 begins toy expose the scavenging ports 29,the. aircompressed during the preceding return stroke of the mobile yunit-in thecollector 23, is thus brought to.V pass tirstly into the cylinder 25,then through the transferduct 28 .provided near tothe cylinder lhead 32,in thef'cylinder'24, this compressed air Vdischarging the burntlgases'while ,assuring the filling of the two said cylinders, and thenonce more to be compressed at theY -moment of the .following return`stroke of the mobilezunit, at the vend 'of which the fuel is injectedAby the pump-injector 36.y v f l As explainedrin theforegolng, ,thedevice is providedv with a yhousing 9 enclosing ka mechanism 10.Thehousing 9r delimitsr a recess, intendedto rcontain a charge-of air, f

for example compressed .by means of a hand pump, and the mechanism 10vcomprises a 'hand-controlled valve which isn'ot shown'fand which"isintended-to allow the putting yinto communication of the recess of thehousing 9--when vwishing to start up the machine-withthe interior'of theVcylinder 5, into which a charge'of compressed `air is'thus injected,.which has the eect of rapidlyy thrustingqthe mobile unit in the.opposite vdirection to that-ofthe arrowV f1, to cause the compressionofthe air a wdege1shape in order to ensure satisfactory combustion ofthe fuel' mixture. In this case, the piston heads 39, 40 arefso shapedas Vto correspond to that of the,

tained in the combustion chambers v41 and 42 begins to.V ignite.Thefcombustionl of Athis mixture has the effect` of thrusting thismobile unit towards the right, i.e., in

the direction of the arrow f1, and hence the air in the cylinder 2 isprogressively compressedY and delivered through theoutlet flapivalve 7'into the collector V6, Y

connected to a tank (not shown). y

During this movement, the 'compressor piston 37 sets up a depression inthe chamber 221'whose Volume isV contained 'in the combustionchambers'41, 42, and consequently, to start oit the linst driving,stroke of the machine. Y v Y e FIGURE 5 showsV a lirst alternativerevealing constructive simplications, enabling the carrying out ofdevices vintended for special purposes.y According to this alternative,the mobile unit comprises only oneY compressor piston137 and a singledriving piston39a, extending coaxially with vsaid compressor pistonv 37.Y According to. this alternative,the cylinder 5, intended to store upthe return power, is. also suppressed, lbutl inthis case, 'the exhaustnap-.valve 7, provided in the cylinder 2 is placed 'at a kcertaindistance from the end of the-latter, in orderto progressivelyincreasing, and consequently,` air is sucked through the Vfilteringcartridge 15, then this air, after f having iiowed over the tins 3 withwhich the compression. casing 1lis provided, penetratesl into saidchamber .222y

obviously raising the inlet ap-valve or hap-valves 13..

The stroke in the'direction of the arrow f1 of the mobiles.v unit hasthe effect, moreover, of compressing the' gars' charge contained in thecylinder 5.' The latter.V being.

closed, a power is thus storedup whichis then utilized, at the end ofthe driving stroke, for returning thefmobile unit to the position shownin the drawing.

During lthe return Vstroke described above, i.e.,.lduring thatcorresponding to the setting ,free of 'the power increase thedetrimental volume, andy consequently, thus create a closed enclosureintended tof'storewup the return power ofthe mobile unit. j l

l As in the example described above, with reference to FIGURES 1 to 4,the air sucked'in and-then compressed is discharged from the chamber 22and directed' by the manifold V23 into thedrivinggcylinder controllingthe drivmg'piston 43, this driving cylinder obviously having the sameexhaust ports 31 which communicate'jwith the manifold 30 acting'fortheevlacuaition of the burnt gases. The

power-driven lcompressor device described above, with reference toFIGURE 5, is particularly simple to. pro- Y duce, and although in actualpractice its., output is slightly stored up inthe cylinder 5, thecompressor piston '37j causes a depression in theY cylinder 2, andconsequently;

airis suckedy through the filtering cartridge 15 and rthrough thechamber 17 while passing throughthe .inlet flap-valves 14. As in thepreceding case, this air lows over the ns of. the compression cylinder,which ensure an efficient cooling of the' latter. .y

lessthan that of the devicepreviously described, this conceptionenablesflowv powered machines to be made in a .very economical mannerthus advantageous for numerous purposes. Y

When it is desirable that the overallvdimensions of the power-drivencompressor should be as smalLas possible and this, while retainingallthe advantages atorded by the device described with reference toFIGURES 1 to 4,

- more pznticularlyV with regard to the advantagesv obtained by thearrangement with two driving cylinders,y itis possibleto form the volumestoring up the return power-as described in FIGURE 5, i.e., byincreasing the detrimental space at the bottom of the compressioncylinder 2 which can be obtained by placing the outlet flap-valve 7lateral- 1y at a certain distance from the bottom. It is also possibleto const-ruct the power-driven compressor as shown diagrammatically inFIGURE 6, in which the various main components shown are denoted by thesame reference numerals as in FIGURES 1 to 4. More particularly, forreducing the length of the power-driven compressor, the sheath 4,confining the cylinder 5 storing up the return power, is suppressed, andin this case, the compression casing 2 is closed by a bottom 44extending level with the annular border 11; this bottom supports twofixed pistons 45 and 46 which penetrate into cavities 47 and 48 madeinside the compressor piston 37 and of each of the two driving pistons39 and 40, said cavities 47 and 48 obviously having variable volumesduring the movement of the mobile unit, and consequently these variablevolumes, previously filled with a charge of air, act as an accumulatingcontainer for the return power to be developed, in order to produce thisdisplacement of said mobile unit in Athe direction for which thiscombustion air must be compressed in the cylinders 24 and 25. Althoughnot shown, the arrangement according to FIG- URE 6 can also be put intooperation in the powerdriven compressor as described with reference toFIG- URE 5, in a power-driven compressor comprising only one drivingpiston and a single compressor piston.

It will be obvious to those skilled in the art that various changes maybe made without departing vfrom the spirit of the invention andtherefore the invention is not limited to what is described in thespecification, but only as indicated in the appended claims.

We claim:

1. A free piston machine comprising a motor casing and a compressioncasing in aligned relationship, a single movable unit located in saidmotor and compression casing to be reciprocated therein, said movableunit cornprising a rst piston located in said compressorcasing anddelimiting therein an inlet scavenging air chamber and a compressionchamber for the compression of at least one charge of gas, at least onemotor piston rigidly connected to said first piston and slidably mountedin said motor casing delimiting a cylinder for said motor piston, acollecting chamber surrounding at least in part said cylinder andscavenging ports communicating said cylinder with said collectingchamber, said scavenging ports being successively closed and uncoveredby said motor piston, a partition provided between said collectingchamber and said inlet scavenging air chamber, valve members mounted insaid partition for communication from said inlet scavenging air chamberto said collecting chamber, said motor cylinder further delimiting anexhaust collector having openings for communication with said cylinder,said openings being successively closed and uncovered by said motorpiston and a channel for location of a fuel injector.

2. A free piston machine comprising a motor casing and -a compressioncasing rigidly connected in aligned relationship and externally providedwith protruding cooling tins, a single movable unit located in saidmotor and compression casing to be reciprocated therein, said movableunit comprising a piston member mounted inside said compression casing,said piston member delimiting respectively on one and the other sidesthereof an inlet scavenging air chamber and a compression chamber forthe compression of at least one charge of gas, said single reciprocableunit further comprising a motor piston rigidly connected to said pistonmember and slidably mounted in said motor casing delimiting a cylindertherefor, said compression casing having outwardly extending ringprojections and an annular sheath provided with a tiltering member beingconnected to said ring projections and delimiting therewith an annularchamber into which project said cooling fins of said casing, inlet valvemembers carried by said compression casing and mounted on both sides ofsaid piston member respectively for communication between said annularchamber and said scavenging air chamber and said compression chamber forsupplying thereof with air respectively during driving and driven strokeof said reciprocable unit, further said motor casing delimiting acollecting chamber at least in part surrounding said cylinder andcommunicating therewith by means of scavenging ports successively closedand uncovered by said piston during reciprocation thereof, cooling tinsprovided inside said collecting chamber and extending substantially inradi-a1 direction with respect to said cylinder for cooling thereof, apartition provided transversely between said collecting chamber and saidinlet scavenging air chamber, valve members mounted in said partitionfor communication from said inlet scavenging air chamber to saidcollecting chamber, said motor cylinder further delimiting an exhaustcollector having openings for communication with said cylinder, saidopenings being successively closed and uncovered by said motor piston,a-nd a fuel injector leading to said cylinder for supplying thereof withfuel.

3. A free piston machine comprising a motor casing and a compressioncasing in aligned relationship, a single movable unit mounted toreciprocate inside said motor and compression casing, said movable unitcomprising a piston member shaped substantially like a piston forcompression in one direction of lat least one charge of gas to becompressed and of at least one supplemental charge of air constituting acushion charge intended to cause said unit to move in an oppositedirection for compression of a charge of scavenging air, said unitfurther comprising two motor pistons integral with said piston memberfor driving thereof, said motor pistons being slidably mounted insidesaid motor casing delimiting two parallely extending motor cylinders, a-collecting chamber at least in part surrounding said cylinders, atransfer channel interconnecting said cylinders near the top partthereof, a fuel supplying recess also interconnecting said cylinders atthe top part thereof, an exhaust collector partially surrounding one ofsaid cylinders, scavenging ports between said collecting chamber and oneof said cylinder, and exhaust openings between said exh-anust collectorand the other cylinder, a partition transversally extending between saidmotor casing and said compression casing, flat valves mounted insidesaid partition for the transfer of said scavenging air compressed bysaid piston member towards said collecting chamber of the motor casing,and inlet and outlet flat-valves carried by said compression casing onboth sides of said piston member for inlet Iand outlet of said chargesof gas to be compressed by said piston member.

4. A free piston machine as set forth in claim 3 in which said pistonmember comprises a fiat piston rigidly connected on one of its sides tosaid motor pistons and a concentrically extending cushion piston ofsmaller diameter ixedely connected to the other side of said fiat pistonand into which further said compression casing delimits a compressioncylinder for said flat piston, fa cushion cylinder for said cushionpiston and a discharge collector, discharge flat valves interposedbetween said compression cylinder and said discharge collector, inletvalve for said compression cylinder a-nd a compressed air supplyingmechanism for said cushion cylinder for the starting of the machine.

5. A free piston machine as set forth in claim 3 in which said pistonmember comprises a flat piston rigidly connected to said motor pistons,and said compression casing delimits a cylinder for said ilat piston andis provided at its bottoms with inlet valve and at a distance apart fromsaid bottom with discharge collector for the air compressed by said flatpiston by which a closed compression chamber for the compressed lair isprovided between said bottom and said discharge valve for compression ofthe charge of air causing the return stroke of the unit.

' l 8 l 6.Y A free piston machine as set forth in claim 3 in ReferencesCited bythe Examiner' which said piston member comprises a flat pistonrigidly UNITED STATES PATENTS connected to said motor pistons 'and saidlcompression r casing delimits a cylinder` for said flat piston and ispro- 2189497 2/,40 Pesca-a- 23o-56 vided at itsV bottom witha-,discharge 'valve for commu- 5 2,435232 2/48 'Mofaln 230-56 nicationwith :a discharge collector for the gas compressed Y 1 l FOREIGN PATENTSby said flat piston,y said flat piston and'motor pistons contnectedtherewith having longitudinally extending bores 1 giggle; and saidcompression casing having cylindrically protrud- 301079 v 5/30 Greattlaiu ing xedly mounted parts at least partially engaged Iinto 10 v f KY said bores and delimiting therewith closed chamber `for LAURENCEVEFNER lPrmmyExmm-Iwr the compression of ther charge of air causing thereturn f y stroke of said movable unit. i ROBERT 1v1-WALKER', Examiner-

1. A FREE PISTON MACHINE COMPRISING A MOTOR CASING AND A COMPRESSIONCASING IN ALIGNED RELATIONSHIP, A SINGLE MOVABLE UNIT LOCATED IN SAIDMOTOR AND COMPRESSION CASING TO BE RECIPROCATED THEREIN, SAID MOVABLEUNIT COMPRISING A FIRST PISTON LOCATED IN SAID COMPRESSOR CASING ANDDELIMITING THEREIN AN INLET SCAVENGING AIR CHAMBER AND A COMPRESSIONCHAMBER FOR THE COMPRESSION OF AT LEAST ONE CHARGE OF GAS, AT LEAST ONEMOTOR PISTON RIGIDLY CONNECTED TO SAID FIRST PISTON AND SLIDABLY MOUNTEDIN SAID MOTOR CASING DELIMITING A CYLINDER FOR SAID MOTOR PISTON, ACOLLECTING CHAMBER SURROUNDING AT LEAST IN PART SAID CYLINDER ANDSCAVENGING PORTS COMMUNICATING SAID CYLINDER WITH SAID COLLECTINGCHAMBER, SAID SCAVENGING PORTS BEING SUCCESSIVELY CLOSED AND UNCOVEREDBY SAID MOTOR PISTON, A PARTITION PROVIDED BETWEEN SAID COLLECTINGCHAMBER AND SAID INLET SCAVENGING AIR CHAMBER, VALVE MEMBERS MOUNTED INSAID PARTITION FOR COMMUNICATION FROM SAID INLET SCAVENGING AIR CHAMBERTO SAID COLLECTING CHAMBER, SAID MOTOR CYLINDER FURTHER TO SAIDCOLLECTING CHAMBER, SAID MOTOR OPENINGS FOR COMMUNICATION WITH SAIDCYLINDER, SAID OPENINGS BEING SUCCESSIVELY CLOSED AND UNCOVERED BY SAIDMOTOR PISTON AND A CHANNEL FOR LOCATION OF A FUEL INJECTOR.